Now that the iPad 2 has a front facing-camera and some decent horsepower under the hood, there's a lot of potential for really interesting camera-plus-screen coordination hacks. The clever folks over at the Engineering Human-Computer Interaction Research group have managed to combine a feed from the front-facing camera, with a bit of software wizardry, to track the position of a person's head in 3D in real-time.

They call it Head-Coupled Perspective, and the result, as you can see above and past the break, is a 3D representation on the 2D screen that moves when you do. Like looking through a small window, the dynamically adapting 3D effect is pretty convincing, at least on camera, and it's not just the iPad 2 that can get in on the action; the iPhone 4 can be kitted out, too. Considering that all you need is a front-facing camera, something that every Apple device capable of running apps already comes packing, we could see some pretty ingenious 3D application interfaces that don't just rely on tilting the device.

Currently, it's just a tech demo, but there's a possibility of an app in the cards for the near future. In the meantime, hit the break to check out HCP in action on the iPad 2.